"These days, owner David Baur spends a lot of time worrying in his full-service garage near downtown Los Angeles. As cars become vastly more complicated than models made just a few years ago, Baur is often turning down jobs and referring customers to auto dealer shops. Like many other independent mechanics, he does not have the thousands of dollars to purchase the online manuals and specialized tools needed to fix the computer-controlled machines.

Baur says the dilemma has left customers with fewer options for repair work and given automakers an unfair advantage.

Many new vehicles come equipped with multiple computers controlling everything from the brakes to steering wheel, and automakers hold the key to diagnosing a vehicle's problem. In many instances, replacing a part requires reprogramming the computers - a difficult task without the software codes or diagrams of the vehicle's electrical wires.

The technology wave has made even the simplest tasks difficult for some ill-equipped mechanics. Baur, for instance, said he couldn't turn off the "check tire pressure" light after fixing a 2008 Mercury Grand Marquis because he lacked the roughly $1,000 tool to reset the tire pressure monitor. The customer said he has to visit the dealer shop to complete the job.

Dealership shops may be reaping profits from the technological advancements. A study released in March by the Automotive Aftermarket Industry Association found vehicle repairs cost an average of 34 percent more at new car dealerships than at independent repair shops, resulting in $11.7 billion in additional costs for consumers annually

... mechanics can't afford to work on all types of cars because vehicles are increasingly built with unique specifications and require their own set of tools. Mechanics must specialize in a select number of models to stay competitive, he said.
Baur said specialization is a luxury he can't afford. He said he bought the garage 20 years ago from a former boss who serviced all kinds of cars.
"What are you going to do? Refuse service to the people who've been coming here all these years?" he said."

Article: To OBD II Or Not. Modern technology versus the value of
very used cars. By: Phil Coconis

"For example, systems involving supplemental restraint (airbag), anti-lock braking, traction control, automatic climate control, collision avoidance, navigation, multi-speed automatic transmission, and vehicle security, while offering added convenience and safety, can be quite costly to maintain and repair. One technology that all new vehicles have, regardless of make or model, is the OBD II, an acronym for a drivetrain and emissions management system that, when spelled out, means On Board Diagnostics-Phase Two. Implemented on all passenger cars since 1995, and light trucks since '96, that are sold in the U.S.A., this system proved to be a quantum leap in capability and complexity compared to the previous OBD I and earlier management systems.

The downside is that, in order to accomplish all of these capabilities, more sub-systems, components (or their improvements), and monitoring software have been added, such as the fuel evaporative leak-detection system and its monitor. Failure sensitivity for other system monitoring, such as for catalytic converters and oxygen sensors, has been increased as well.

OBD II Obstacles
In real world terms, for example, this means that a Check Engine MIL (Malfunction Indicator Lamp) might illuminate if the fuel filler cap is not completely tightened, or the catalytic converters are operating much below 95 percent efficiency. In both cases, a trip to a qualified repair shop will be needed for diagnosis and, in the case of the former, resetting the check monitors. The latter would likely require replacement of the catalytic converter(s), a prospect considerably more expensive than on pre-OBD II vehicles.

If the state or area you live in has an I/M (emission Inspection/Maintenance or smog) test, an illuminated Check Engine MIL will result in a failure of the test. The difference with OBD II vehicles is that just resetting the self-test monitors to turn off the lamp will not allow your vehicle to pass the test, even if the measured tailpipe emissions are within prescribed limits.

The reason is that part of the I/M test on OBD II vehicles involves the test technician connecting his test machine's data link with the serial data port on the vehicle. If the self-test monitors have just been reset (generally within the past 50 miles), they will show a "not-ready" status, which will prevent the technician from certifying the vehicle. Rules are rules. So the vehicle will have to be driven long enough under a variety of driving conditions in order to "arm" the self-test monitors. If the problem that originally caused the MIL to illuminate is still present, the lamp will once again illuminate.

OBD I Pros
In contrast, pre-OBD II vehicles are not tested in such a stringent fashion. If the MIL is functional, but not illuminated during the test, and the vehicle passes the visual, functional, and tailpipe portions of the test, it qualifies for certification-even if there is a pending problem. When you consider that many catalytic converter replacements can cost well over $1,000, you can start to see the wisdom in owning a pre-OBD II vehicle.
Because of the OBD II issue, as well as the other considerations we discussed, purchasing an older vehicle may make sense for many people. This is not to say, however, that just any older vehicle will automatically be a better choice. Obviously, certain models, while perhaps evoking nostalgic feelings in us, no longer qualify as practical for daily use, or are not economically justifiable at this point in time.

It isn't difficult, though, to spot the vehicles that are. Generally, if the manufacturer and model have a good reputation, and there is an abundance of this model to choose from, that's a good sign. Survival of the fittest definitely applies here. Of course, it won't guarantee that all existing examples of the vehicle are worthy. As with any used vehicle purchase, employ due diligence by weeding out the bad ones by a process of thorough inspection. Purchasing an older used vehicle might not be "nobler in the sight of all men," but it can pay big dividends in the long run.

Don't have a late model vehicle? Maybe you are better off than you think!

Recently I stopped in at a local garage to say, "Hi" to the owner. He was removing covers -- or something --
from the shiny clean engine. I said, "Got troubles?" He said, "No. Just changing spark plugs." I peered into the engine-well and asked, "Spark plugs? Where are the spark plugs?"
He replied, "Under all this xxxx. Huh, changing spark plugs is as simple as it always was ----- if you can find
them. Ain't nothing simple anymore."